The present invention relates to an architecture, embodied either in hardware or a software agent or in a combination of hardware and software, adapted to develop reflexes and, more particularly, conditioned reflexes.
The interest of such an architecture is two-fold. Firstly, by being able to develop conditioned responses which are linked to unfulfilled operational requirements (needs), an architecture of this type can maximise the probability of satisfaction of its requirements and thus maximise its operational efficiency, for example, by increasing the duration of its useful working life. Secondly, an architecture having reflexes which are conditioned, at least in part, by externally-given user inputs, appears to the user to be exhibiting behaviour in a quasi-social manner. Such an observation leads to the experiencing by the user of a feeling of sympathy towards the machine or programme embodying the architecture. This type of sympathetic response to the architecture is something which has long been viewed as a desirable goal in the field of artificial intelligence (A.I.). One of the reasons why this goal is highly valued, is that it is generally considered that the user who feels sympathy towards a machine or software agent will better cooperate with that machine or software agent in the achievement of a common task. Moreover, the user will find working with this machine or software agent to be more congenial.
In the field of artificial intelligence, it has already been proposed to create architectures which, based on sensory inputs, can exhibit behavioural patterns which, to a human observer, appear to denote intelligence. See, for example, xe2x80x9cA Robust Layered Control System For A Mobile Robotxe2x80x9d by R. A. Brooks, IEEE Journal of Robotics and Automation, RA-2(1):14-23, 1986. Brooks"" creatures are based on a so-called subsumption architecture and, based on a small set of primitive behaviours, without symbolic expression, they exhibit apparently very complex behaviour. Brooks"" work represents an example of behaviour-based artificial intelligence.
However, in order for human user to feel sympathy towards a machine or software agent, it is not sufficient for that machine or software agent to exhibit behaviour which appears to be intelligent, it is also important that there should be an inference of emotion. This has been seen, for example, from the work of Bates (xe2x80x9cThe Role of Emotion in Believable Charactersxe2x80x9d by J. Bates, Communication of the ACM 37(7):122-125, 1994). Bates was interested in creating animated characters which would be considered to be believable by human users. His xe2x80x9cbelievablexe2x80x9d characters attracted people because they appeared to imitate human-like expressions of emotion and, thus, to show an xe2x80x9cillusion of lifexe2x80x9d. The importance of this inference of emotion in attracting or creating the sympathy of human users has also been shown by other studies such as the xe2x80x9cNeurobabyxe2x80x9d project (xe2x80x9cNeurobabyxe2x80x9d by N. Tosa in Visual Proceedings of SIGGRAPH-93 Tomorrow""s Realities. ACM SIGGRAPH, 1993) and the ALIVE project (xe2x80x9cSituation Action: A Symbolic Interpretationxe2x80x9d by Percy Maes in Communications of the ACM 38(11):108-114). Moreover, the degree of attachment which humans can develop for animated characters which exhibit an xe2x80x9cillusion of lifexe2x80x9d is seen from the fact that many owners of Tamagochi(trademark) cry when the animated character embodied therein xe2x80x9cdiesxe2x80x9d.
The present invention is based on a model which postulates that emotional expressions in humans are rooted in the experiencing of bodily needs. Although, it is clear that the needs of computers and software agents are different from those of humans, the architecture of the present invention implements an approach which metaphorically resembles that of humans when experiencing bodily needs, according to the postulated model.
More particularly, the present invention provides a system adapted to develop reflexes conditioned by experience, comprising: at least one application module having an operational requirement and adapted, when said operational requirement is not satisfied, to output a signal indicative of a need condition; a regulatory unit adapted to receive said need signal and to produce a control signal leading to a manifestation, perceptible to an external agent or user, of the existence of an unsatisfied operational requirement; input means for detecting an input or event of external origin, said input or event being adapted to cause the operational requirement of said application module to be satisfied; a conditioning unit adapted to receive signals indicative of the existence of unsatisfied operational requirements in application modules of said system, signals indicative of the manifestation perceptibly to external agents or users of the existence of the unfulfilled operational requirement, signals indicative of the detection of satisfaction inputs or events of external origin, and to generate a signal indicating the probability of satisfaction of a present unsatisfied operational requirement based on values of said received signals for previous unsatisfied operational requirements; wherein at least one unit in the system adapts its operation as a function of the value of said expectation signal.
By developing reflexes, especially reflexes conditioned by the reaction of human users or other non-human agents with which the architecture interacts, directed at the satisfaction of unsatisfied operational requirements (needs), the architecture according to the present invention optimises the chances of obtaining satisfaction of its operational requirements and exhibits a behaviour which, to a human observer, implies the existence of emotional states. This latter feature leads to a feeling of sympathy in the human user towards the machine or software agent embodying the architecture.
Other advantageous features of embodiments of the invention are recited in the dependent claims appended hereto.